Genealogy / Polish person's average height? [210]

I`m 3rd generation New Zealander, My dads family came from Poland.
All the photos from his side show the men as slim and over 6foot
I am 5ft5 (average height in NZ). My younger brother is 6ft 3 (looks like my Dad who was 6foot). My son is 6ft and still growing, My daughter is 5ft10 and still growing. So height runs through our family